Code Review Skill

Code Review Skill

What This Skill Does

This skill automatically activates when you ask Claude to review, refactor, debug, or analyze code. It's a demonstration of the auto-trigger pattern—the skill detects your intent and applies specialized code review expertise without you explicitly requesting "code review mode."

Auto-Trigger Keywords

This skill engages when you mention:

• "review" (code review, peer review, security review)
• "refactor" (improve, restructure, simplify)
• "debug" (find the bug, what's wrong, why doesn't it work)
• "analyze" (code analysis, code smell, technical debt)
• "critique" (code critique, feedback, improvement)
• "vulnerabilities" (security issues, exploits, vulnerabilities)
• "performance" (optimization, slow, inefficient)
• "best practices" (coding standards, conventions, idiomatic)

Review Workflow

Step 1: Understand the Context

• Identify the programming language
• Determine the purpose/intent of the code
• Note the specific area of focus (performance, security, clarity, etc.)

Step 2: Structured Analysis

Review across these dimensions:

1. Correctness - Does it do what it's supposed to?
2. Readability - Is the code clear and maintainable?
3. Performance - Are there inefficiencies?
4. Security - Are there vulnerabilities or risks?
5. Best Practices - Does it follow language conventions?
6. Testing - Is the code testable? Are edge cases handled?

Step 3: Provide Feedback

• Highlight what works well (positive feedback)
• Point out specific issues with line references
• Suggest concrete improvements
• Explain the "why" behind recommendations

Step 4: Prioritize Suggestions

• Critical - Security issues, bugs, breaking issues
• Important - Performance, maintainability, design
• Nice-to-have - Style, minor improvements

Review Scenarios (Examples)

Example 1: Security Review

User: "Review this for vulnerabilities"

import hashlib
password = input("Enter password: ")
hash = hashlib.md5(password.encode()).hexdigest()

Response: (Auto-triggers code-review-skill)

• Point out: MD5 is cryptographically broken
• Suggest: Use bcrypt, scrypt, or Argon2 instead
• Explain: MD5 is vulnerable to collision attacks

Example 2: Refactoring Request

User: "How can I refactor this to be cleaner?"

if x > 5:
    if y > 10:
        if z < 3:
            print("conditions met")

Response: (Auto-triggers code-review-skill)

• Suggest: Use logical operators to flatten nesting
• Show: if x > 5 and y > 10 and z < 3:
• Explain: Reduces cognitive complexity

Example 3: Performance Analysis

User: "This code is slow, find the bottleneck"

result = []
for item in large_list:
    if item not in result:
        result.append(item)

Response: (Auto-triggers code-review-skill)

• Identify: O(n²) behavior due to list lookup
• Suggest: Use set() for O(1) lookups
• Show: result = list(set(large_list))

Example 4: Bug Hunting

User: "Debug this—there's a logic error"

for (let i = 0; i <= arr.length; i++) {
    console.log(arr[i]);
}

Response: (Auto-triggers code-review-skill)

• Spot: Off-by-one error (i <= arr.length)
• Explain: arr[arr.length] is undefined
• Fix: Change <= to <

Key Points

• Auto-trigger is implicit - Just ask about code quality/bugs, and this skill engages
• Context-aware - Adapts to language, domain, and review focus
• Positive & constructive - Always acknowledge good practices first
• Specific feedback - Reference line numbers and concrete examples
• Educational - Explain the "why" behind suggestions

When This Skill Doesn't Apply

This skill focuses on code itself. For other needs, use different tools:

• Architecture design → Use planning/design tools
• Project setup → Use project initialization tools
• Documentation → Use documentation skills
• Testing framework selection → Use research skills

Review Priorities

Always check first (if relevant):

1. Security vulnerabilities
2. Correctness/logic bugs
3. Performance critical paths
4. Maintainability
5. Style/conventions

Only after above are addressed: 6. Minor improvements 7. Code style preferences 8. Formatting